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code 542 real or ghost?

  • Thread starter Thread starter saleener94
  • Start date Start date Jan 17, 2008
S

saleener94

Member
Apr 24, 2006
153
1
17
Compton,CA
Jan 17, 2008
#1
  • Jan 17, 2008
  • #1
Hi guyz. I'm getting code 542 after replacing fuel filter and using inertia switch to shut off fuel pump. I also just put my catted h-pipe back on for smog. (542=fuel pump secondary circuit open or grounded. I cleared it with my scanner but i'm worried it might come back. Is this normal to give code 542 after shutting off fuel pump this way? Car is running fine. And will it affect smog check even though CEL is off?
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
18
108
Chicagoland
Jan 18, 2008
#2
  • Jan 18, 2008
  • #2
A lot of the time (if not most), it's just a ghost code. The fuel pump relay might have had a slight delay when latching, or even could have been caused by the inertia switch? If you have a 5 speed and stalled it at all, I believe that has been known to cause the 542 as well. I wouldn't lose any sleep over it.
 
S

saleener94

Member
Apr 24, 2006
153
1
17
Compton,CA
Jan 18, 2008
#3
  • Jan 18, 2008
  • #3
Thanx Stang. I feel better knowing that its common. I'll read the codes again just to see if it's back.
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
18
108
Chicagoland
Jan 18, 2008
#4
  • Jan 18, 2008
  • #4
It should remain until you clear it out, but if it doesn't return, it probably just was a ghost code.
 
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